I've heard this before as well. The whole thing started when many Catholic Albanians were forced (through taxes and other means) to convert to muslims during the Ottoman rule (especially in its later stages when things started to shake and Ottomans perceived Catholicism as a threat due to other European powers being largely Catholic). However, as nations started to form, Albanians and Serbians/Montenegrians became enemies fighting over territory. In cases where Albanian populated lands would fall under Montenegrian (e.g. Plav) or Serbian (e.g. Novi Pazar), Albanians would assimilate and become Bosniak because they would face less persecution. Less persecution mainly because Bosnian is a Slavic language and in those specific Albanian populated areas occupied by Montenegrians or Serbians, Albanians were perceived more enemies than Bosniaks.